1. Field of the Invention
The present invention relates to a network infrastructure integrated system, and particularly, to a network infrastructure integrated system which integrates a telephone line network and an electric power line network separately installed in a home into a single network.
2. Description of the Background Art
As data communication systems become more highly developed recently, in order to efficiently use systems connected to different respective networks from each other, network users share applications and data included in the respective networks by integrating the respective networks into a single network. The users share the applications and data, whereby the cooperation of the respective systems are performed, and the users are able to use the respective systems more efficiently. Therefore, between the systems connected to respectively different networks from each other, interexchangeability of the applications and data should be maintained using protocols made by standardization authorities.
As described above, communication is an essential factor in everyday life and is being developed continually. Therefore, the development of communication skills increases the needs of the usual users for information, and the users can use multimedia services in their home using the Internet. Especially, some users try to construct a network infrastructure system which is easily accessed even in a small space or in their home.
Accordingly, users are able to construct a home network system using wireless devices, telephone lines, or power lines, and are able to receive/transfer audio information, video information, and data file information at a high speed.
FIG. 1 shows a general home network infrastructure system. As shown therein, the system includes a gateway system 10 connected to the PSTN (Public Switched Telephone Network) and to the Internet and converting communication protocols therebetween; a telephone line network 20 connected to the gateway system 10 and constituting a separate network using the telephone line wiring in the home; a plurality of PNA (Phoneline Networking Alliance) modems 30A, 30B, . . . , and 30N; Home Information Machines 40A, 40B, . . . , and 40N (for example, a personal computer, a printer, or a video camera, etc.); a power line network 60 constituting another separate network using the power lines in the home; a plurality PLC (Power Line Communication) modems 70A, 70B, . . . , 70N connected to the power line network 60 and modulating/demodulating data signals transmitted and received therethrough; a plurality of Home Information Machines 80A, 80B, . . . , 80N transmitting/receiving data signals modulated/demodulated through the PLC modems 70A, 70B, . . . , 70N; and a router 50 transferring/receiving data signals between the telephone line network 20 and the power line network 60.
Operation of the conventional network infrastructure integrated system constructed as above will now be described.
Generally, the data signals transmitted over the home network include a header information portion and a data information portion. The header information portion includes a destination information of where the data signal is intended to arrive, and the data signal portion includes an address of a terminal such as the Home Information Machines 40 or 80 where the data signal is intended to arrive. Therefore, when the user wants to transfer data from an Home Information Machine connected to the telephone line network 20 to an Home Information Machine connected to the telephone line network 20 and to the power line network 60, and to an Home Information Machine (not shown) connected to another home network, the data signal is modulated in the PNA modem 30A connected to the Home Information Machine 40A, and then the data signal is broadcasted to all Home Information Machines (40B, 40C, . . . , 40N, 80A, 80B, . . . , 80N) connected to the telephone line network 20 and to the power line network 60 and broadcasted to the gateway system 10 through the telephone line network 20. Hereinafter, this process will be described in more detail as follows.
1) in order to transfer the data signal which is broadcasted to the Home Information Machines 40B, 40C, . . . , 40N connected to the telephone line network 20, first, the data signal is transferred to the PNA modems 30B, 30C, . . . , 30N connected to the telephone line network 20 through the telephone line network 20.
The PNA modem 30 is standardized by a standardization authority as a Home PNA, and it connects information communication appliances into a single network using the telephone lines installed in the home. That is, users can share a printer, peripheral appliances, files, application programs, and play network computer games by connecting to the Internet via the telephone line network 20 using the PNA modem 30 based on the Home PNA standard, and home automation can be made. In addition, voice and video data can be transferred using IP(Internet Protocol), and at the same time a phone call can be made. In order to perform these operations, the PNA modems 30A, 30B, . . . , 30N include information of the addresses of the Home Information Machines 40A, 40B, . . . , 40N connected to them, and the transferring speed is 10 Mbps.
Therefore, the PNA modems 30B, 30C, . . . , 30N compare the addresses of their connected Home Information Machines 40B, 40C, . . . , 40N with the destination information of the received data signal. At that time, the PNA modem 30B connecting the Home Information Machine 40B which has the same address and the destination information as the received data signal, demodulates the data signal and transfers the data signal to the Home Information Machine 40B connected to the PNA modem 30B. However, the other PNA modems 30C, 30D, . . . , 30N connected to the telephone line network 20 do not have same addresses of the Home Information Machines connected to them as the destination information, and accordingly, ignore the data signal.
2) In order to transfer the broadcasted data signal to the Home Information Machines 80A, 80B, . . . , 80N connected to the power line network 60, the data signal is transferred to the router 50 through the telephone line network 20.
The router 50 includes a PNA modem 30 and a PLC modem 70, and the PNA modem 30 included in the router 50 demodulates the data signal and transfers it to the PLC modem 70. The PLC modem 70 in the router 50 modulates the data signal for transmission without noise in the signal on the power lines. After that, the router 50 broadcasts the data signal to the respective Home Information Machines 80A, 80B, . . . , 80N installed on the power line network 60. Therefore, the data signal is transferred through the power line network 60 to the PLC modems 70 connected to the power line network 60.
The PLC modem types are classified into a modem for high voltage lines, for a low voltage lines, and for home power lines. The PLC modem 70 for home power lines modulates/demodulates a high frequency carrier of hundreds KHz˜tens MHz with the data signal so as to be transferred over the power lines carrying alternating current of 50˜60 Hz, and includes addresses of the Home Information Machines connected to itself.
However, the PLC modem is not standardized, and it requires sophisticated technology, so accordingly it is not generally suitable for the high quality communication network.
The PLC modems 70A, 70B, . . . , 70N connected to the power line network 60 compare the addresses of the Home Information Machines 80A, 80B, . . . , 80N connected to them with the destination information of the received data signals. The PLC modem 70A having connected to it a machine having the same address as the destination information demodulates the data signal and transfers it to the Home Information Machine 80A connected to the PLC modem 70A. However, the other PLC modems 70B, 70C, . . . , 70N connecting to the power line network 60 those machines which have different addresses from the destination information of the data signal, ignore the data signal.
3) In order to transfer the broadcasted data signal to other Home Information Machines (not shown) connected to an external network, the data signal is transferred to the gateway system 10 through the telephone line network 20.
The gateway system 10 includes a PNA modem 30 connected with the external network, and the data signal is demodulated in the PNA modem 30 and converted into a protocol suitable for the external network and transferred to the Home Information Machines (not shown) connected to the external network.
4) In order to transfer a data signal from a Home Information Machine (not shown) connected to another home network, from another Home Information Machine 40B, 40C, . . . , 40N connected to the telephone line network, or from the Home Information Machines 80A, 80B, . . . , 80N connected to the power line network to the Home Information Machine 40A, the data signal is transferred in the opposite order from 1), 2), and 3) above.
However, in the network infrastructure system according to the conventional art, the router 50 is expensive, whereby the economical efficiency is lowered. In addition, if the user wants to construct a home network using only the telephone line network 20, additional wiring is needed because the telephone lines in the home typically have fewer connection terminals (jacks) than the power lines and telephone line connection terminals (sockets)do not exist in many places.